This paper is concerned with the issue of public – private divide within the theory of organization. The main argument is that with administrative development and change, the definition of public, as opposed to private organization, also changes. Current state of public administration is characterized by the blurring of boundaries between public and private sectors. Due to such development the approach to public – private distinction had change. Traditionally, public organizations were identified as public on the basis of formal, legal criteria of ownership: organizations in the property of the state were considered public, and those in the private ownership, private. Modern public administration challenges this formula. Thus, it is possible to
distinguish four approaches in the conceptualization of publicness of an organization: the oldest, formal approach, dimensional, normative and integrative approach.